Finger Wrench (digit spanner)

thingiverse

When you're stuck in a tight spot trying to attach a nut to a bolt, a finger wrench can be just what you need. Tight corners are especially challenging, and anywhere that requires reaching into unknown territory: dropping a spanner down the back of a radiator is all too easy, but dropping your finger is not. I recently discovered this handy little gadget on a DIY blog, unfortunately, the company that originally supplied it is no longer in business (why not?) and I couldn't find anywhere to purchase existing stock. I had to have one, so I designed and 3D printed my own version, and it works like a charm! Here's how to use it: there's a gap all along the back side of the wrench, allowing one size to fit a wide range of fingers. Simply slip a nut or bolt into the wrench as shown in the images. Finger pressure keeps the nut or bolt in place, while the tapered slot inside the wrench prevents it from turning. This finger wrench is suitable for 1/2-inch nuts and bolts and smaller. To print it, use PLA or ABS material with 0.2mm layer thickness and 100% infill for strength. UPDATE: I've upgraded the design to a 'Pro' version. The new design is sleeker and more ergonomic on the finger. You can download the updated file, FingerWrench_Pro.stl. Thanks to MD80 for inspiring this design with their own creation on Thingiverse. UPDATE: Bitschieber suggested an additional feature - a version with more finger tip control for smaller fasteners. I've added that to the design as well. DISCLAIMER: Please don't use this item with impact wrenches or air-powered tools - you might end up destroying the Finger Wrench and, more importantly, your finger! Enjoy!